Unbolt the headbolts?
On my last Supra when we removed the head all we did was remove everything restricting the head from being removed. Such as fuel lines, ect. Just remove the valve covers and take off the head bolts if you have everything out of the way.
Such as
Fuel lines, wiring harnesses, plugs, hoses, and so fourth.
Then head bolts and BAM. But I would recommend removing the headbolts in the TSRM pattern and using a torque wrench.
Just from experience
-Matt